[Logeshsharma]

Handle ScanQrCode emitted by the Thunderbird account setup flow so the QR import screen opens when no account is configured.

Contribution Summary

Linked Issue/Ticket: Fixes #11276

Description

Handle ThundermailRoute.ScanQrCode in the launcher navigation flow.

Previously, when no account was configured, the account setup flow emitted
ThundermailRoute.ScanQrCode, but the launcher did not handle that route and
the action fell through without navigation.

This adds the missing navigation branch so the QR import screen opens correctly.

Screen Recording

handle.QR.code.navigation.mp4

Testing

• Reproduced the issue with no configured accounts.
• Verified that Scan QR code opens after the fix.
• Verified that the existing-account QR flow still works.
• I couldn't find existing tests covering this launcher navigation path. Happy to add regression coverage if there is a preferred testing approach for this area.

AI Disclosure

Select one of the following (mandatory)

• This contribution does not include any changes created or assisted by AI.
• This contribution includes changes assisted by AI.
• This contribution includes changes created by AI.

Contribution Checklist

• I have read and affirm that my contribution adheres to Mozilla’s Community Participation Guidelines
• This contribution is in Kotlin where possible
• This contribution does not use merge commits
• This contribution adheres to the existing codestyle (run gradlew spotlessCheck to check and gradlew spotlessApply to format your source code; will be checked by CI).
• This contribution does not break existing unit tests (run gradlew testDebugUnitTest; will be checked by CI).
• This contribution includes tests for any new functionality, and maintains tests for any updated functionality.
• This contribution adheres to our Engineering process (RFC/Technical Design/ADR)
• This PR has a descriptive title and body that accurately outlines all changes made, and contains a reference to any issues that it fixes (e.g. Closes #XXX or Fixes #XXX).

[github-actions]

✅ Validation Passed: All report and feature-flag labels are correctly set.

[rafaeltonholo]

LGTM! Thanks for this contribution

[thunderbird-botmobile]

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